/*
 * Copyright (c) 2011-2012 Alexander Dubu
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * o  Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *
 * o  Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 *
 * o  Neither the name Axil nor the names of its contributors may be used to
 *    endorse or promote products derived from this software without specific
 *    prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
package axil.stdlib.collection.type;

import axil.api.AxilObject;
import axil.api.AxilType;
import axil.framework.type.AbstractType;
import axil.framework.type.NativeEquivalent;
import axil.stdlib.text.type.Str;

import java.util.Dictionary;
import java.util.HashMap;

import static axil.framework.Functions.axil;


/**
 * Type metadata for the map collection. Do NOT create an instance of this
 * class. No good can come from it. Only access to the type metadata from the
 * value class.
 */
class Dict_Type extends AbstractType implements NativeEquivalent {
    public static final String PAIR_SEPARATOR = ",";
    public static final String KEY_VALUE_SEPARATOR = "->";
    static final AxilType object = new Dict_Type();


	private Dict_Type() {
		super("dictionary");
	}


	/**
	 * Get the list of native Java types that this type is equivalent to. The
	 * list returned is never null nor empty.
	 */
	public Class[] natives() {
		return new Class[] {HashMap.class, Dictionary.class};
	}


	/**
	 * Parse the given text as a representation of the canonical form of this
	 * type. A null is returned if the text does not represent a valid object.
	 * The string given cannot be null.
     *
     * The format for a single key-value pair is "key -> value". pairs are separated by commas.
	 */
	public AxilObject parse(String text) {
		String[] parts = text.split(PAIR_SEPARATOR);
		Dict<Str,Str> a = new Dict<Str, Str>();
		for (String s : parts) {
            String[] pairParts = s.trim().split(KEY_VALUE_SEPARATOR);
            if (pairParts.length != 2)
            {
                // Not a valid format, returning null.
                return null;
            }
            Str k = Str.from(pairParts[0].trim());
            Str v = Str.from(pairParts[1].trim());
            a.at(k, v);
		}
		return a.immute();
	}


	/**
	 * Transform the given native object into its equivalent value object. The
	 * object given is never null and is guaranteed to be one of the alias types
	 * indicated by this object's type (as reported by the typeof() method).
	 */
	public AxilObject transform(Object object) {
		java.util.Map o = (java.util.Map)object;
		Dict m = new Dict();
		for (Object key : o.keySet()) {
			m.at(axil(key), axil(o.get(key)));
		}
		return m.immute();
	}
}
